Google thrives where privacy does not. If you're like most internet users, Google knows more about you than you might be comfortable with. Whether you were logged in to a Google account or not, they know everything you've ever searched for, what search results you clicked on, what news you read, and every place you've ever gotten directions to. Most of the time, thanks to things like Google Analytics, they even know which websites you visited that you didn't reach through Google. If you use Gmail, they know the content of every email you've ever sent or received, whether you've deleted it or not.

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GoogleSharing is a system that mixes the requests of many different users together, such that Google is not capable of telling what is coming from whom.